This is because the problem is with the "identity theory" itself, not what exactly the "material" relatum amounts to, with which the "qualia" are supposed to be identical. As Monk rightly sums up:
One might say: qualia are a suspect kind of entity anyway, so why should I need a theory to account for them? Fine, but what you can't say is: these qualia you talk about, they just are these coding vectors, and then act like you've explained qualia [...] Similarly [i.e. to a deleted example, which doesn't seem quite right], one can say: I can explain everything there is to explain about sensation without reference to "qualia", so why should I be obliged to give you a separate explanation of them? But that is not what is being offered. Rather, we are told, color qualia exist; they are cone cell coding vectors.Okay, but I think Monk actually lets Churchland off the hook. I would rather he had stayed with the promising line that explaining sensory experience isn't a matter of either
a) a complete neurophysical explanation, such as the materialist gives us; or
b) (a), corresponding to the "objective" part of the phenomenon in question, plus an explanation of "qualia," or the "subjective" part, where this latter part may simply be ineffable, but in any case necessary, such that without it we have an "explanatory gap".
But instead, he goes into Ned Block mode, telling us essentially that Churchland's proposal leaves something out.
When is Churchland going to wake up and smell the coffee? I'm not sure, but I don't think we should test it by asking him whether he's awake or not; better check his brain scan and let him know. Then do an EEG and see if he's smelling the coffee. With sufficient training he could be taught to look at the EEG and say, "Why, I was smelling coffee!" (This is the flip side of Churchland's utopia, in which we are all so well-informed about cognitive facts that introspection itself becomes a recognition of coding vectors and the like.) Now for the tricky part: turn off the switch in his brain that produces the coffee-smelling qual, and tell him that every morning, rather than having that phenomenological version of the sensation, he will recognize the coffee smell intellectually and be shown a copy of his EEG. And similarly, one by one, for all his other qualia.This is the same thing everybody says about the Churchlands. (Not the same, but it reminds me of the joke about the behaviorists in the bedroom: "It was good for you; was it good for me too?") It wasn't to the point then, and it's not to the point now. It's true that the materialist answer "leaves something out" conceptually; but the reply cannot be that we can bring this out by separating the third-personal and first-personal aspects of coffee-smelling, and then (by "turn[ing] off a switch in his brain") give him only the former and see if he notices anything missing. That the two are separable in this way just is the Cartesian assumption common to both parties. (Why, for example, should we expect that if he simply "recognize[s] the coffee smell intellectually" his EEG wouldn't be completely different from, well, actually smelling it?) I think we should instead resist the idea that registering the "coffee smell" is one thing (say, happening over here in the brain) and "having [a] phenomenological version of the sensation" is a distinct thing, one that might happen somewhere else, such that I could "turn off the switch" that allows the latter, without thereby affecting the former. That sounds like the "Cartesian Theater" model I would have thought we were trying to get away from.
But rejecting this suspect idea is not at all to return to saying, with the materialist, that (what I called) "registering" the smell and "subjectively experiencing" it are identical, such that we only need the former (so construed). Sensory experience (like cognition and every other "mental" phenomenon) has multiple aspects, of which the "purely" first-person and "purely" third-person aspects are merely the ones most ripe for illegitimate philosophical reification. Better far to tell a story such that these are more easily seen as useful abstractions from a more unitary phenomenon. (On the other hand, go too far in this direction, and you get a big monistic mess, in which subject and object disappear entirely. Opinions differ about Dewey, but Experience and Nature at least threatens to have this result. Subject talk and object talk are indispensable, and we need not render them inaccessible simply in order to block their dualistic reification. But that's another story for another day.)
Don't say: well, he doesn't deny these qualia exist, after all; he just thinks they are identical to blah-blah-blah... If he thinks they are identical to blah-blah-blah then he should not object in the least if we can produce blah-blah-blah without those illusory folk-psychological phenomena we think are the essence of the matter.Interestingly, I was at a talk one time where Churchland said just that very thing ("I love qualia!") to Block's predictable objection. (He and Block went back and forth a few times, neither understanding the other, until everybody else started fidgeting.) I'm not defending his answer, except to the extent that I agree that Block's objection is not the right response. Churchland will just say that you can't produce one without the other, because (as I also agree) there's no distinct "experiencer" in the brain; and we shouldn't let him get away with that. After all, we're after the conceptual issue, not the empirical one; and all the proposed experiment would get Churchland to do (if it "worked" at all) is to abandon his empirical proposal that that particular neural candidate was the correct one. All you will have shown is that that neural candidate wasn't sufficient for smelling, when it's the very idea of "identifying" subjective and objective aspects of experience which is incoherent.
Look also at how easy it is, even while saying something basically right, to slip into misleading ways of talking. Monk is rejecting the idea that Churchland's claimed ability to use his neural theory of sensory experience to make "phenomenological prediction from neurological facts" provides any support for it (i.e. for the idea that "the qualia-coding vector relationship is not a mere correlation but an actual identity"). We can do that already, without needing to posit a tendentious "identity" to account for it. Here's Monk's example:
We know that the lens of the eye delivers an inverted image, which is subsequently righted by the brain. This suggests that our brains, without our conscious effort, favor a perspective that places our heads above our feet. (It is also possible that it is simply hard-wired to invert the image 180 degrees, but for various reasons that theory does not hold water.) Prediction: make someone wear inverting glasses, and they will see [an] upside down image at first (the brain inverts it out of habit), but eventually the brain will turn it right side up. It works!Again, I agree with the general point: we don't need any "identity" here. But the wording seems to leave some of the generating assumptions in place. The lens of the eye does indeed "deliver an inverted image" to the retina (we can even see it, back there). But why say that that image "is subsequently righted by the brain"? Does it need to be "righted" ... in order for us to see it? Again we have an incipient Cartesian Theater. Surely what we see is not the image, but the objects in front of us. Inverting glasses make it seem as if everything is upside down; but after a while we get better at (re-)coordinating our various sensory inputs (primarily vision, touch, and proprioception), and that impression fades (not that one image is replaced by another). There: I told the story "without giving a separate explanation" of the visual anomaly; isn't that what we were supposed to do, rather than demanding a distinct something lacking from the materialist account? It's not a detailed story, as the solely neural one would be; but so what? We can give details on request, depending on the point of the question, and maybe this will require one sort of abstraction from our unified picture, and maybe it'll require a different one. That doesn't mean they're separable (as the qualophile demands).
Churchland also claims, Monk tells us, that "trained musicians 'hear' a piece differently than average audiences." I don't see how this was supposed to help Churchland's case, but Monk objects to the very idea:
That is also a predictable phenomenological fact, but it involves a change in the mental software, through accustomization and training, and does not obviously involve any sensual change. To see a new color or to have fewer distinct sounds reach the brain from the cochlea are sensual changes; to hear more deeply those sounds that do reach the ear, to organize them more efficiently and recognize more relationships between is not a sensual change but an intellectual one that we might metaphorically characterize as "hearing more than others". In fact musicians hear the same thing others hear but understand what they hear in a more lucid way. The sensual phenomena I have mentioned are actual changes in what reaches the brain for processing or in processing at a subliminal level, and do not depend on how we train ourselves to organize the information we receive.Again, I don't see why we need a dualism between "sensual changes" (i.e. in the sound that reaches the ear) and "hearing [these sounds] more deeply". (Isn't that the fallacy behind the philosophical chestnut "if a tree falls and no-one hears it, does it make any sound?"). I don't see any reason that we are required to say that "musicians hear the same thing others hear," simply because there's a sense (the "objective" one?) in which it's trivially true. As an English speaker, I find it perfectly straightforward (i.e. not necessarily metaphorical) to say that musicians "hear more than others." Nor do I feel obliged to characterize the difference as "intellectual" rather than "sensual," even if the latter sort of change is due to one of the former sort.
So what's the moral? Maybe it's this. In situations like this, it will always seem like there's a natural way to bring out "what's missing" from a reductive account of some phenomenon. We grant the conceptual possibility of separating out (the referent of) the reducing account from (that of) the (supposedly) reduced phenomenon; but then rub in the reducer's face the manifest inability of such an account to encompass what we feel is "missing." But to do this we have presented the latter as a conceptually distinct thing (so the issue is not substance dualism, which Block rejects as well) – and this is the very assumption we should be protesting. On the other hand, what we should say – the place we should end up – seems in contrast to be less pointed, and thus less satisfying, than the "explanatory gap" rhetoric we use to make the point clear to sophomores, who may very well miss the subtler point and take the well-deserved smackdown of materialism to constitute an implicit (or explicit!) acceptance of the dualistic picture.
Surely there's a way to make this point in the Wittgensteinian language of aspect-seeing, but I haven't got it just right yet. How about this: that I see the picture-duck only in seeing the drawing – that the former doesn't ontologically "transcend" the latter, if you like – doesn't mean I have to say they're identical (as the materialist-analogue would have it). If I do that, then I have to tell the same story about the picture-rabbit. But the picture-duck isn't "identical" with the picture-rabbit, which it would have to be if both were identical with the drawing.
But now the solution to this is not to say instead that the picture-duck is different (i.e. a distinct thing) from the drawing, while yet being careful to say (now as the Block-analogue would have it) that the former doesn't after all "transcend" the latter in a metaphysically unpleasant way. In a sense it was right to say that the picture-duck "is" the drawing; the problem was with the nature of that "is". (It depends on what the meaning of "is" is (heh heh).) It's not the "is" of "objective" metaphysical identity; it's the "is" of aspect recognition ("that drawing? It's a duck").
Try it with a different "is" still. The drawing is a picture-duck. Now we have the "is" of predication. It's also a picture-rabbit; but in each case we have the same drawing. That sounds okay at first; but it leaves us with a scheme-content dualism. The experience of aspect-dawning is one of seeing a different picture, not of seeing the same picture differently. Seeing the "same drawing" is too far in one direction, while seeing distinct entities is too far in the other. Or, to sound a Wittgensteinian note from another context: the difference between the picture-duck and picture-rabbit is "not a something, but not a nothing either." (I blush to admit that I can't remember exactly where this line occurs. My defense is that it applies to so much of what he says that it might occur anywhere. Anyone?)
Yet Wittgenstein himself sometimes seems dogmatically to close off what might, if properly conceived, be possible empirical/scientific investigations. This offends my pragmatist sensibilities (Peirce: thou shalt not put roadblocks on the path of inquiry). Here's an example from PI p. 211e:
The likeness makes a striking impression on me; then the impression fades.I like that; but right before this he says:
It only struck me for a few minutes, and then no longer did.
What happened here?—What can I recall? My own facial expression comes to mind; I could reproduce it. If someone who knew me had seen my face he would have said "Something about his face struck you just now."—There further occurs to me what I say on such an occasion, out loud or to myself. And that is all.—And this is what being struck is? No. These are the phenomena of being struck; but they are 'what happens'.
Is being struck looking plus thinking? No. Many of our concepts cross here.
"Just now I looked at the shape rather than at the colour." Do not let such phrases confuse you. [So far so good; but now:] Above all, don't wonder "What can be going on in the eyes or brain?"In a way this is right too, in the way the first excerpt was right. Don't wonder that if you thought that was going to provide the answer to our conceptual problem. But surely there is something going on in the brain! Would you tell the neuroscientist to stop investigating vision? Or even think of him/her as simply dotting the i's and crossing the t's on a story already written by philosophy? That gets things backwards. Philosophy doesn't provide answers by itself, to conceptual problems or scientific ones. It untangles you when you run into them; but when you're done, you still have neuroscience to do. Neuroscience isn't going to answer free-standing philosophical problems; but that doesn't mean we should react to the attempt by holding those problems up out of reach. Instead, we should get the scientist to tell the story properly, so that the problems don't come up in the first place. (Wittgenstein credits this insight to Hertz, but we will leave that story for someone more qualified than I to tell.)